Connector, method of making connector and tubing assembly method

ABSTRACT

A fitting or connector for use in constructing a tubing assembly is made by bonding an olefin gasket to an end face of a polypropylene fitting member. The gasket is bonded to the fitting member via a heat fusion technique that causes localized melting together of the gasket and the fitting and generates a composite fitting or connector.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 62/585,154 filed Nov. 13, 2017, the entire disclosure ofwhich is hereby incorporated by reference.

FIELD OF THE INVENTION

The invention relates to tubing systems used to transport fluidicmaterials in the manufacture, for instance, of pharmaceuticals andmedicaments. More particularly, this invention relates to a fitting orconnector used to couple tubing sections to form a fluid transportcircuit. This invention also relates to a method for manufacturing thefitting or connector. This invention further relates to associatedmethods of constructing tubing systems.

BACKGROUND OF THE INVENTION

For as long as drug products have been manufactured, the Biotech andPharmaceutical industry used various methods to convey liquid productsduring the drug manufacturing process. In more recent years theindustry's mindset has been to move away from traditional processeswhich relied on fixed capital intensive piping systems. Traditionalsystems are typically made from stainless steel or glass lined piping.Because these systems were capital intensive, drug manufacturers wouldgo to large expense to validate cleanability and ensure no crosscontamination from one batch to the next. Facility owners have had toinvest in expensive large and sophisticated utility plants with chemicaldosing systems and ultra-high purity steam systems necessary tosterilize the systems.

More recently manufacturing methods have trended to faster drugdevelopment and faster regulatory clearance to market. This trend is inconjunction with, and partially due to, world health authoritiesgranting fast track approvals of vaccines and therapies to combat thenew strains of mutated diseases, which are arising more frequently.

Today, many of the new drug manufacturing processes utilize “Single UseSystems”. These are basically pre-sterilized sub-systems manufacturedfrom plastics. They are used once, or a limited number of times, andthen discarded. For example, instead of a stainless steel vessel andpiping, a typical single use system would consist of a number of plasticbag(s) connected by a series of plastic tubing sets with mechanicalconnection means, including tubing manifolds, between bags, tubes andother system components. Concern over the seal integrity on tubingmanifolds is of paramount concern. Manifolds are constructed usingfittings to connect multiple incoming and outgoing tubing lengths invarious configurations.

Because of their high temperature rating, Stainless Steel Piping Systemsare typically sanitized by methods of hot water or “Steam in Place”(SIP). Plastic systems are typically sterilized by different methods andcomponents are replaced more frequently, thereby reducing potentialcontamination from incomplete cleaning of the system between batches.

Single use plastics offer many other advantages. Components may costless and can be manufactured in desired shapes by a multitude ofmanufacturing methods, including molding. In biopharmaceuticalprocessing systems, plastics are typically sterilized by means of Gammaor electron-beam irradiation, or Autoclave.

There is a need in the industry for systems, components and methods thathelp avoid system contamination while minimizing build cost, build time,cleaning cost, system defects and environmental impact.

The typical end configuration used to join devices and tube ends is the“sanitary,” also known as the “tri-clamp,” design, which uses aface-seal gasket between two mating components. The gasket and fittingsare separate components. Until the installation is complete, the facesof the fittings and gaskets are vulnerable to outside contamination.Installation of the gasket requires handling that also increases risk ofcontamination.

In addition, low-profile, translucent gaskets can be difficult to see,particularly in a clean-room environment where operators wear gowns,gloves and sometimes eye protection. Missing gaskets can go unnoticed.

Gaskets and fitting face designs have not been fully standardized in theindustry. The degree of standardization of plastic components lagsbehind that of stainless steel products. For this reason users currentlymust take care in selecting and testing combinations of systemcomponents, fittings and gaskets. Sealing performance may vary dependingon fitting manufacturer and gasket manufacturer. Small changes in acomponent can lead to system problems or require re-validation.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide an improved fittingfor connecting lengths of tubing in a fluid flow system used in themanufacture of pharmaceuticals and medicaments.

It is a related object of the present invention to provide an improvedmethod for connecting lengths of tubing in a fluid flow system used inthe manufacture of pharmaceuticals and medicaments.

An associated object of the present invention is to provide an improvedmethod for manufacturing a fitting for connecting lengths of tubing in afluid flow system used in the manufacture of pharmaceuticals andmedicaments.

Another object of the present invention is to provide such a fitting andsuch methods that help avoid system contamination while minimizing buildcost, build time, cleaning cost, system defects and environmentalimpact.

SUMMARY OF THE INVENTION

The present invention is directed in part to a method of manufacturing afitting or connector for use in constructing a tubing assembly. Themethod comprises providing a fitting member including a plurality ofends with respective openings that communicate with one another via alumen of the connector member, one of the ends being formed with an endface. The method further comprises providing a gasket, disposing thegasket against the end face, and bonding the gasket to the end face ofthe fitting member to form a fluid-tight seal between the gasket and theend face of the fitting member.

Pursuant to a feature of the present invention, the bonding of thegasket to the end face of the fitting member includes applying energy toat least one of the gasket and the fitting member to sealingly fuse thegasket to the end face. In particular, the applying of energy includeselevating a temperature of the gasket and/or the fitting member to heatfuse the gasket to the end face of the fitting member.

Preferably, the gasket is made of a first polymeric material and thefitting member is made of a second polymeric material different from thefirst polymeric material. The first polymeric material is typically moreflexible and deformable that the second polymeric material. The applyingof energy to the gasket and/or the fitting member preferentiallyincludes an applying of heat energy in an amount to induce a microscopicor molecular-level mixing of the first polymeric material with thesecond polymeric material at an interface between the end face of thefitting and the gasket to produce a density or concentration gradient ofthe first polymeric material and an oppositely directed density orconcentration gradient of the second polymeric material between thegasket and the fitting member. In brief, the gasket is bonded to thefitting member via a heat fusion technique that causes localized meltingtogether of the gasket and the fitting and generates a composite fittingor connector. In the composite fitting or connector, the gasket face ofthe fitting member is soft and pliable and that material graduallymerges with the more rigid material of the fitting member. The fittingmember becomes a unitary object with different part of the unitaryobject having different physical characteristics.

In a preferred embodiment of the present invention, wherein the end ofthe fitting member face is provided with a recess and the gasketincludes a pair of major surfaces, one of the major surfaces including aprojection, the disposing of the gasket against the fitting end faceincludes disposing the projection in the recess. The mating projectionand recess serve to facilitate alignment and registration of the gasketwith the end face of the fitting member prior to and during the bondingprocess. (The mating features may be dispensed with where ancillaryexternal support and fixation devices are used to ensure mutualalignment and registration of the gasket and the fitting member.) Themixing of polymeric material and concomitant gradient generation caneffectuate an obliteration of the structural idiosyncrasies of thegasket and the fitting member at the interface therebetween. Inparticular, any projection on the gasket and an associated receptiverecess on the fitting member end face may disappear.

A fitting or connector for use in constructing a tubing assemblycomprises, in accordance with the present invention, a fitting memberincluding a plurality of ends with respective openings that communicatewith one another via a lumen of the connector member. The fitting memberis provided at one of the ends with a gasket bonded to the fittingmember so as to form a fluid-tight seal between material of the gasketand material of the fitting member. Where the gasket is made of a firstpolymeric material and the fitting member is made of a second polymericmaterial different from the first polymeric material, the gasket ispreferably fused to the fitting member so that it is impossible todetect where the fitting member ends and the gasket begins. The firstpolymeric material is mixed with the second polymeric material at aninterface between the fitting member and the gasket to produce a densityor concentration gradient of the first polymeric material and anoppositely directed density or concentration gradient of the secondpolymeric material between the gasket and the fitting member.

Pursuant to a preferred feature of the present invention, the firstpolymeric material is olefin and the second polymeric material ispolypropylene.

It is a preferred, but not required, feature of the present inventionthat the gasket includes a major surface on a side opposite the fitting,with that major surface including a projection. It is a more particularfeature of the present invention that the projection is an annular ribor bead which is receivable in an annular groove in an additionalfitting member. The two fitting members cooperate to form a joint in ahydraulic or fluid-conveyance circuit.

The gasket is preferably heat fused to the fitting member.

In accordance with another feature of the present invention, the fittingmember or preform is a T fitting having two end openings defining aflow-through pathway and a third end opening laterally of saidflow-through pathway. The gasket is attached at the end of the fittingmember or preform which has the third end opening. The gasket includes afluid-impermeable diaphragm at least coextensive with a central openingof the gasket, whereby the gasket provides a seal and impediment tofluid flow. The T composite fitting or connector is preferably used forattachment of a gauge or measurement device to a tubing assembly.

In accordance with another feature of the present invention, the gasketincludes a web member at least coextensive with a central opening of thegasket, where the web member is a diaphragm, a screen, or a perforatedplate.

A method of constructing a connector and tubing assembly comprises, inaccordance with the present invention, providing a first fitting orconnector member including a plurality of ends with respective openingsthat communicate with one another through a lumen of the first fittingor connector member, the first fitting or connector member beingprovided at one of the ends with a gasket bonded to the first fitting orconnector member so as to form a fluid-tight seal between material ofthe gasket and material of the fitting or connector member. The methodfurther comprises providing a second fitting or connector memberincluding a plurality of ends with respective openings that communicatewith one another through a lumen of the second fitting or connectormember, the second fitting or connector member having an end face. Themethod also comprises juxtaposing the first fitting or connector memberand the second fitting or connector member so that the end face (of thesecond fitting or connector member) is in contact with the gasket(bonded to the first fitting or connector member), and coupling thefirst fitting or connector member and the second fitting or connectormember to one another to form a fluid tight seal between the end faceand the gasket.

Where the gasket is made of a first polymeric material and the firstfitting or connector member is made of a second polymeric materialdifferent from the first polymeric material, the gasket is preferablyheat fused to the first fitting or connector member. In that case, thefirst polymeric material is mixed with the second polymeric material atan interface between the first fitting or connector member and thegasket to produce a density or concentration gradient of the firstpolymeric material and an oppositely directed density or concentrationgradient of the second polymeric material between the gasket and thefirst fitting or connector member.

Pursuant to a preferred feature of the present invention, the couplingof the first fitting or connector member and the second fitting orconnector member to one another is implemented by placing a clamp aboutjuxtaposed ends of the first fitting or connector member and the secondfitting or connector member and locking the clamping about thejuxtaposed ends of the first fitting or connector member and the secondfitting or connector member.

A preferred embodiment of the present invention is, accordingly, apolypropylene fitting and thermoplastic olefin gasket with fitting endgeometry and gasket geometry, before fusion, essentially matching, orvery similar to, common sanitary “tri-clamp” characteristics, such asASME BPE standard configuration for steel fittings with gaskets.

A method for use in constructing a connector and tubing assemblycomprises, in accordance with the present invention, providing a T-typefitting or connector member having two end openings defining aflow-through pathway and a third end opening lateral to the flow-throughpathway. The fitting or connector member is provided at the third endopening with a gasket bonded to the fitting or connector member so as toform a fluid-tight seal between material of the gasket and material ofthe fitting or connector member. The gasket includes a fluid-impermeablediaphragm at least coextensive with a central opening of the gasket,whereby the gasket provides a seal and impediment to fluid flow. Themethod further comprises juxtaposing an access port of a gauge ormeasurement device with the gasket bonded to the fitting or connectormember and removably coupling the gauge or measurement device to thefitting or connector member to form a fluid tight seal between the gaugeor measurement device and the gasket.

A tubing assembly component, for use in assembling a tubing circuit,comprises, in accordance with the present invention, a fitting membersuch as (a) a tubular member with two or more ports or (b) an end capfor use in closing off an unused port, where the fitting member is madeof hard polymeric material such as polypropylene and is provided with agasket made of a different, soft and pliable polymeric material such asolefin, with the gasket bonded to the fitting member so as to form afluid-tight seal between material of the gasket and material of thefitting member.

In summary, the present invention is directed to an elastomer gasketheat-fused to a rigid polymer fitting. Fusing the two componentseliminates two exposed faces and the corresponding sealing interface.This integration of the gasket into the fitting member, forming agasket-fitting composite substantially reduces risk of contamination inhandling and of leakage in use. There is no handling of a separategasket. Installation is simplified. Risk of connections missing gasketsis eliminated. Performance risks related to selection and variation ofmating components are eliminated for that interface. Where the gaskethas an impermeable membrane or diaphragm and is used at a gauge ordevice coupling point, the degree of cleanliness of the gauge is nolonger crucial, as the gauge does not come into contact with the sterileinterior surfaces of the tubing and fittings.

Because the gasket is fused, it cannot separate in shipping orpreparation. It is impossible to install a fitting with no gasket.

An instrument fitting pursuant to the present invention was developed asa means to maintain a sterile barrier where disposable manifolds areused on hybrid single-use process equipment. Fixed or tetheredpressure-monitoring devices provide extremely high accuracy and areoften hard wired into a central control panel. The present instrumentfitting provides a practical means of maintaining a sterile barrier on acomplex manifold set, and ensures a barrier without the need to have agauge present during the sterilization process.

A fitting in accordance with the present invention incorporates anelastomeric, e.g., TPE (Cellgyn™), gasket fused into a singular sanitaryfitting, forming a one-piece composite design. The result is a genderedfitting that can be used in conjunction with any standard sanitaryconnection. It provides superior ergonomics and less risk ofcontamination.

A composite fitting or connector in accordance with the presentinvention is formed without the use or application of solvents, glues oradhesives. A composite fitting or connector in accordance with thepresent invention may provide gendered connection that works with anynon-gendered sanitary connection.

The present invention fulfills a long-standing need in the industry—asevidenced by the problems solved by the invention. No manufactureroffers a sanitary fitting with an elastomeric gasket permanently affixedto its face. At least one manufacturer offers plastic sanitary fittingswith mechanically affixed gaskets of dissimilar materials. One suchexisting design comprises a gasket with special features thatmechanically attach to special tabs on a fitting. This design has thedisadvantage that the gasket can separate from the fitting duringshipping, handling or installation, exposing the two mating faces topotential contamination. This may lead to a false sense that the gasketwill always be attached.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front, left side and top perspective view of a fittingmember used in constructing a fitting or connector in accordance withthe present invention.

FIG. 2 is a rear, left side and top perspective view of the fittingmember of FIG. 1.

FIG. 3 is a side elevational view of the fitting member of FIGS. 1 and2.

FIG. 4 is a front elevational view of the fitting member of FIGS. 1-3.

FIG. 5 is a rear elevational view of the fitting member of FIGS. 1-4.

FIG. 6 is a longitudinal cross-sectional view of the fitting member ofFIGS. 1-5, taken along line VI-VI in FIG. 5.

FIG. 7 is a top perspective view of a gasket or sealing ring used inconstructing a fitting or connector in accordance with the presentinvention.

FIG. 8 is a front elevational view of the gasket or sealing ring of FIG.7.

FIG. 9 is a side elevational view of the gasket or sealing ring of FIGS.7 and 8.

FIG. 10 is a cross-sectional view of the gasket or sealing ring of FIGS.7-9, taken along line X-X in FIG. 8.

FIG. 11 is a front, left side and top perspective view of a fitting orconnector in accordance with the present invention, assembled from thefitting member of FIGS. 1-6 and the gasket or sealing ring of FIGS.7-10, that also represents a preliminary stage in manufacturing aconnector or composite fitting member in accordance with the invention.

FIG. 12 is a rear, left side and top perspective view of the fittingmember of FIG. 11.

FIG. 13 is a side elevational view of the fitting member of FIGS. 11 and12.

FIG. 14 is a front elevational view of the fitting member of FIGS.11-13.

FIG. 15 is a rear elevational view of the fitting member of FIGS. 11-14.

FIG. 16 is a longitudinal cross-sectional view of the fitting member ofFIGS. 11-15, taken along line XVI-XVI in FIG. 15.

FIG. 17 is a front, left side and top perspective view of a fitting orconnector in accordance with the present invention, a modification ofthe embodiment of FIGS. 11-16.

FIG. 18 is a rear, left side and top perspective view of the fitting orconnector of FIG. 17.

FIG. 19 is a side elevational view of the fitting or connector of FIGS.17 and 18.

FIG. 20 is a front elevational view of the fitting or connector of FIGS.17-19.

FIG. 21 is a rear elevational view of the fitting or connector of FIGS.17-20.

FIG. 22 is a longitudinal cross-sectional view of the fitting orconnector of FIGS. 17-21, taken along line XXII-XXII in FIG. 20.

FIG. 23 is a front, left side and top perspective view of a pair ofjuxtaposed fittings or connectors including the fitting or connector ofFIGS. 17-22, aligned with one another for forming a joint in afluid-flow tubing system.

FIG. 24 is a rear, left side and top perspective view of the juxtaposedfittings or connectors of FIG. 23.

FIG. 25 is a side elevational view of the juxtaposed fittings orconnectors of FIGS. 23 and 24.

FIG. 26 is a front elevational view of the juxtaposed fittings orconnectors of FIGS. 23-25.

FIG. 27 is a longitudinal cross-sectional view of the juxtaposedfittings or connectors of FIGS. 23-26, taken along line XXVII-XXVII inFIG. 26.

FIG. 28 is an elevational plan view of juxtaposed fittings or connectorsin accordance with the present invention, with adjacent and alignedflanges disposed in a recess in an opened tubing clamp.

FIG. 29 is a side elevational view of the juxtaposed fittings orconnectors and open tubing clamp of FIG. 28.

FIG. 30 is a longitudinal cross-sectional view of a T fitting member orpreform, similar to the views of FIGS. 6, 16, 22, and 27, for attachmentor installation of a gauge or measurement device to a tubing assembly.

FIG. 31 is a perspective view of the T fitting member or preform of FIG.30.

FIG. 32 is a transverse cross-sectional view, similar to FIG. 10, of agasket which is permanently attachable to the fitting member of FIGS. 30and 31 pursuant to the present invention, where the gasket includes aliquid-impermeable diaphragm.

FIG. 33 is an exploded view of a gauge or measurement device and acomposite fitting or connector manufactured from the fitting member ofFIGS. 30 and 31 and the gasket of FIG. 32.

FIG. 34 is a perspective view of a gasket provided in a central openingwith a filter screen, which gasket may be incorporated into a compositefitting or connector in accordance with the present invention.

FIG. 35 is a perspective view of a gasket provided in a central openingwith a thin perforated plate, which gasket may be incorporated into acomposite fitting or connector in accordance with the present invention.

FIG. 36 is cross-sectional views of a circular end cap that may beattached over an unused port in a tubing system, the end cap including afused and integral gasket pursuant to the present invention.

FIG. 37 is a transverse cross-sectional view, similar to FIG. 32,showing a modified gasket which is permanently attachable to the fittingmember of FIGS. 30 and 31 pursuant to the present invention, where thegasket includes a liquid-impermeable diaphragm.

FIG. 38 is partial view of a composite fitting or connector manufacturedfrom the fitting member of FIGS. 30 and 31 and the gasket of FIG. 37.

DETAILED DESCRIPTION

As illustrated in FIGS. 1-6, a fitting member 20 for use in formed orassembling fluid flow conduits for particular, although not exclusive,use in the manufacture of medicaments consists of an injection moldedbody member of a relatively stiff and form-maintaining polymericmaterial such as polypropylene. Body member 20 is provided at one endwith a conical formation 22 and at an opposite end with acircumferential flange 24. Flange 24 is formed on an outer surface,facing in a direction opposite conical formation 22, with an annulargroove 26 and is integral on an opposite side with a conical portion 28that in turn is integral with conical formation 22 via a cylindricalsegment 30. A second circumferential flange 32 may be provided, forinstance, at the junction or intersection of conical portion 28 andcylindrical segment 30. Flange 32 has a beveled or rounded circularouter perimeter 34.

Conical end formation 22 and flange 24 define respective openings 23 and25 that communicate with one another via a lumen 27 of the fittingmember.

As depicted in FIGS. 7-10, a gasket or O-ring sealing element 36, whichis preferably made of a flexible or deformable polymeric material suchas olefin, comprises a planar base member 38 formed on opposing majorfaces (not designated) with a pair of annular ribs or beads 40 and 42.Ribs or beads 40 and 42 are typically of the same size and profile butmay be provided with differing sizes and shapes, as well as locationsrelative to base member 38. Ribs or beads are shown as centrallylocated. However either one or the other may be of larger or smallerdiameter and disposed exemplarily along a circular outer edge orcircular inner edge of base member 38.

As shown in FIGS. 11-16, a composite fitting or connector 44 comprisesgasket or O-ring 36 disposed along an outer annular surface or end face46 of flange 24, with one of the annular beads or ribs 40 and 42 seatedinside groove 26. Gasket or O-ring 36 is bonded to the end face 46 offitting member 20 to form a fluid-tight seal between the gasket and theend face of the fitting member. The bonding of gasket or O-ring 36 toannular surface or end face 46 of fitting member 20 may include applyingenergy to gasket 36 and/or fitting member 20 to sealingly fuse thegasket to the fitting end face. In particular, the applying of energyincludes elevating a temperature of at least one of the gasket and thefitting member to heat fuse the gasket 36 to the end face 46.

FIGS. 17-22 show an embodiment of a composite fitting or connector 50having a main body 52 made of a hard or stiff polymeric material such aspolypropylene and an annular bead or rib 54 projecting from a flange 56at one end of the fitting or connector. Bead or rib 54 is made of aflexible, resilient and deformable material such as olefin.

Fitting or connector 50 is made by a process as described hereinabovewith reference to FIGS. 11-16. More particularly, in the process formanufacturing composite fitting or connector 50 heat is applied in suchan amount or intensity that a reformation or fusing occurs between agasket preform (not separately visible in FIGS. 17-22 owing to aheat-induced reformation of the component parts) and a fitting preform,namely, main body 52. The applying of energy to at least one of thegasket preform (which similar to, but includes some geometricmodification of, gasket or O-ring 36) and the main-body fitting member52 preferentially includes an applying of heat energy in an amount toinduce a microscopic or molecular-level mixing of the olefin material ofthe gasket with the polypropylene material of the main-body fittingmember 52 at an interface between an end face (see end face 46) of themain body 52 and the gasket to produce a density or concentrationgradient of the olefin polymer and an oppositely directed density orconcentration gradient of the polypropylene between the gasket preformand the main body 52. In an intermediate plane the densities orconcentrations of the olefin polymer and the polypropylene aresubstantially equal on average. From a macroscopic observational pointof view, the gasket loses its separate identity and merges with orbecomes a feature of the main body 52 or fitting. The composite fittingor connector 50 is a hard or stiff member provided with a soft ordeformable bead or rib 54, as well as resilient outwardly projectingannular flange 56, which is soft and pliable on the end face carryingthe fused gasket.

Main body 52 of fitting or connector 50 has the same structure asfitting member 20 described above with reference to FIGS. 1-6. Likereference numerals are used to designate like parts.

FIGS. 23-27 depict composite fitting or connector 50 in juxtaposition toand linearly aligned with a second fitting member 60, with annular beador rib 54 seated in an annular groove 62 on an end face 64 of the secondfitting member. This second fitting 60 is made of a stiff polymericmaterial (e.g., polypropylene) throughout. A liquid-tight seal is formedbetween fittings or connectors 50 and 60 owing to the incorporation of agasket or sealing ring, including bead 54, into the structure of fittingor connector 50.

Fitting or connector 60 has the same basic structure as fitting member20 described above with reference to FIGS. 1-6. Like reference numeralsare used to designate like parts. In their juxtaposition, fittings orconnectors 50 and 60 form a central flange 66 which is received in anannular recess of a hinged clamp 68 shown in FIG. 28. Clamp 68 includestwo generally C-shaped halves 70 and 72 each with a C-shaped recess 74(only one shown) in which the composite central flange 66 is seated.Upon a pivoting closure of clamp halves 70 and 72 and a tightening of alocking wing nut 76, clamp 68 serving in part to press the two fittingsor connectors 50 and 60 together and induce the gasket end of fitting 50to deform against the end face 64 of fitting 60 to create a better seal.

As illustrated in FIGS. 30-33, a composite fitting or connector 102(FIG. 33) for use in assembling a fluid flow circuit exemplarily in themanufacture of medicaments and pharmaceutical compositions comprising afitting member or preform 104 (FIGS. 30 and 31) of a hard polymericmaterial such as polypropylene and a gasket preform member 106 (FIG. 32)of a soft pliable polymeric material such as olefin, bonded andpreferably heat fused to one another so that the material of the gasket106 mixes with the material of the fitting member 104 along an interfacebetween the two elements, as described hereinabove.

Fitting member 104 is a T fitting defining a linear flow-through pathwayor lumen segment 108 extending between two openings 110 and 112 atopposite ends. The fitting member includes a third opening 114 at an end116 of a lateral branch or stem 118 of the T fitting, which defines anancillary lumen or tributary liquid channel lateral to the flow-throughpathway 108.

Gasket 106 comprises an annular body or ring 120 provided on opposinglateral faces (not designated) with annular beads or ribs 122 and 124.Disposed within a center opening 126 of gasket 106 and coextensive withthe opening is a diaphragm 128 in the form of a web of impermeablepolymeric material bonded around its periphery to body or ring 120.Preferably, diaphragm 128 is disposed to one side of gasket 106,substantially coplanar with one of the two opposing lateral faces ormajor surfaces. This offset of diaphragm 128 from a center plane of thegasket ensures a positive marriage between the diaphragm and a sanitarygauge. The offset eliminates a gap or space that becomes filled withair. Air being compressible hinders or reduces gauge accuracy. Inaddition, a greater force is required to move the diaphragm. At lowpressures, a centered diaphragm would prevent the gauge from readinganything at all.

Gasket 106 is heat fused to fitting member 104 so as to form afluid-tight seal between material of the gasket and material of thefitting member. In a tubing circuit assembled to include compositefitting or connector 102, one juxtaposes an access port 130 of a gaugeor measurement device 132 with the gasket 106 bonded to fitting member104 and removably couples the gauge or measurement device 132 tocomposite fitting or connector 102 to form a fluid tight seal betweenaccess port 130 of the gauge or measurement device and the gasket 106.It is not necessary to assiduously sterilize or clean the gauge ormeasurement device prior to attachment thereof to fitting or connector102 as sterility of the fluid flow system will be maintained by theintegrated diaphragm 128.

FIG. 34 depicts a gasket 134 provided in a central opening 136 with afilter screen 138. FIG. 35 shows a gasket 140 provided in a centralopening 142 with a thin plate 144 provided with one or more perforations146. Gasket 134 or 140 may be incorporated into a composite fitting orconnector by heat fusing as described hereinabove.

FIG. 36 depicts a circular end cap 148 that may be attached over anunused port in a tubing system. End cap 149 including a gasket portion150 of soft polymeric material (e.g., olefin) heat fused and integratedwith a body member portion 152 of hard polymeric material (e.g.,polypropylene) as described above. A projection such as an annular ribor bead 154 may be included as an integral part of gasket portion 150and concomitantly of end cap 148. End cap 148 may be used to close offunused ports in an assembled tubing system.

FIG. 37 illustrates a modified gasket preform member 206 of a softpliable polymeric material such as olefin that is bondable to fittingmember or preform 104 (FIGS. 30 and 31) in substitution for the gasketpreform member 106 of FIG. 32. Gasket preform member 206 comprises anannular body or ring 220 provided on opposing lateral faces 252 and 254with annular beads or ribs 222 and 224. Disposed within a center opening226 of gasket 206 and coextensive with the opening is a diaphragm 228 inthe form of a web of impermeable polymeric material, particularlyolefin, heat bonded around its periphery to body or ring 220. Diaphragm228 is disposed to one side of gasket 206, so that an outer surface 250is substantially coplanar with lateral face or major surface 252 of ring220. This offset of diaphragm 228 from a center plane of gasket 206ensures a positive marriage between the diaphragm and a sanitary gauge,e.g., 132 (FIG. 33), eliminating a gap or space that would otherwisefill with air.

Like gasket 106, gasket 206 is heat fused to fitting member 104 so as toform a fluid-tight seal between material of the gasket and material ofthe fitting member, as shown in FIG. 38. Gasket 206 may be provided withan annular nipple 256 projecting from the apex of annular bead or rib224. Nipple 256 melts quickly at the commencement of a heat fusingprocedure to form a thin film between bead or rib 224 and an annulargroove 258 provided in end 116 of a lateral or stem 118 of the T fitting104 (see FIG. 30). The film enhances contact between gasket 206 and thefitting (e.g., T fitting 104), particularly between bead or rib 224 andgroove 258. The film also promotes heat fusion of the two elements.

Care must be taken during the heat fusion process to restrict the heatapplication to the ring bodies 120, 220 so that the diaphragms 128, 228are insulated from the heat energy. Otherwise the diaphragms can warpand distort. An insulation shield (not shown) may be positioned aroundthe diaphragms 128, 228 during the heat fusion procedure.

Although the invention has been described in terms of particularembodiments and applications, one of ordinary skill in the art, in lightof this teaching, can generate additional embodiments and modificationswithout departing from the spirit of or exceeding the scope of theclaimed invention. For instance, the gasket preform (e.g., 36) used toform a composite fitting or connector member pursuant to the presentinvention may have any suitable configuration of body, flange andprojecting elements. The side of the gasket that faces away from thefitting member may have a plurality of pegs or lugs. Likewise thefitting or connector may be provided with any suitable geometry. Thefitting member or preform and the gasket preform may be provided withany surface configuration at the surface or sides that are placed intocontact as that surface configuration is consumed or reshaped inside thefused joint. Projections may serve a temporary function duringmanufacture of facilitating registration or alignment of the gasketpreform and the fitting preform Accordingly, it is to be understood thatthe drawings and descriptions herein are proffered by way of example tofacilitate comprehension of the invention and should not be construed tolimit the scope thereof.

1. A method of manufacturing a fitting or connector for use inconstructing a tubing assembly, comprising: providing a fitting memberincluding a plurality of ends with respective openings that communicatewith one another via a lumen of said fitting member, one of said endsbeing formed with an end face; providing a gasket, said gasket beingmade of a first polymeric material and said fitting member being made ofa second polymeric material different from said first polymericmaterial, said gasket including a fluid-impermeable diaphragm at leastcoextensive with a central opening of said gasket, whereby said gasketprovides a seal and impediment to fluid flow; disposing said gasketagainst said end face; and bonding said gasket to said end face of saidfitting member to form a fluid-tight seal between said gasket and saidend face of said fitting member, the bonding of said gasket to said endface of said fitting member including applying heat energy to both saidgasket and said fitting member to cause localized melting together ofsaid first polymeric material and said second polymeric material at saidend face to heat fuse said gasket to said end face, while leaving saiddiaphragm fluid impermeable.
 2. (canceled)
 3. (canceled)
 4. The methoddefined in claim 1 wherein the applying of heat energy to ef said gasketand said fitting member includes applying heat energy to both saidgasket and said fitting member in an amount to induce a mixing of saidfirst polymeric material with said second polymeric material at aninterface between said end face and said gasket to produce a density orconcentration gradient of said first polymeric material and anoppositely directed density or concentration gradient of said secondpolymeric material between said gasket and said fitting member.
 5. Themethod defined in claim 4 wherein said end face is provided with a firststructural feature taken from the group consisting of a recess and aprojection, said gasket including a first major surface and a secondmajor surface opposed to one another, said first major surface includinga second structural feature taken from the group consisting of aprojection and a recess, the disposing of said gasket against said endface including matingly engaging said first structural feature and saidsecond structural feature with one another.
 6. (canceled)
 7. The methoddefined in claim 5 wherein said diaphragm is disposed to one side ofsaid gasket and has a surface substantially coplanar with said secondmajor surface.
 8. A method of manufacturing a fitting or connector foruse in constructing a tubing assembly, comprising: providing a fittingmember made of a first polymeric material and including a plurality ofends with respective openings that communicate with one another via alumen of said fitting member, one of said ends being formed with an endface; providing a gasket made of a second polymeric material differentfrom said first polymeric material and having a central opening;disposing said gasket against said end face; and heating said gasket andsaid fitting member to cause localized melting together of said firstpolymeric material and said second polymeric material and therebybonding said gasket to said end face of said fitting member to form afluid-tight seal between said gasket and said end face of said fittingmember, wherein said gasket includes a web member at least coextensivewith said central opening of said gasket, said web member being takenfrom the group consisting of a screen and a perforated plate each havingan array of through holes preformed prior to the heating of said gasketand said fitting member, the bonding of said gasket to said end face ofsaid fitting member being performed so as to retain said web memberextending across said central opening.
 9. A fitting or connectorassembly for use in constructing a tubing assembly, comprising: afitting member including a plurality of ends with respective openingsthat communicate with one another via a lumen of said fitting member,said fitting member being provided at one of said ends with a gasketbonded to said fitting member so as to form a fluid-tight seal betweenmaterial of said gasket and material of said fitting member, said gasketincluding a fluid-impermeable diaphragm at least coextensive with acentral opening of said gasket, whereby said gasket provides a seal andimpediment to fluid flow through an opening at said one of said ends,wherein said gasket is made of a first polymeric material and saidfitting member is made of a second polymeric material different fromsaid first polymeric material, said gasket being heat fused to saidfitting member so that said first polymeric material and said secondpolymeric material melt into one another; and a gauge or measurementdevice coupled to said fitting member at said one of said ends so thatsaid gasket and said diaphragm isolate said gauge or measurement devicefrom fluid flow in said fitting member.
 10. The fitting or connectordefined in claim 9 wherein said first polymeric material is mixed withsaid second polymeric material at an interface between said fittingmember and said gasket to produce a density or concentration gradient ofsaid first polymeric material and an oppositely directed density orconcentration gradient of said second polymeric material between saidgasket and said fitting member.
 11. The fitting or connector defined inclaim 9 wherein said gasket includes a major surface on a side oppositesaid fitting, said major surface including one of an annular rib or beadand an annular groove which is respectively receivable in one of anannular groove and an annular rib or bead in an additional fittingmember.
 12. (canceled)
 13. The fitting or connector defined in claim 9wherein said fitting member is a T fitting having two end openingsdefining a flow-through pathway and a third end opening laterally ofsaid flow-through pathway, said one of said ends exhibiting said thirdend opening, said gasket including a fluid-impermeable diaphragm atleast coextensive with a central opening of said gasket, whereby saidgasket provides a seal and impediment to fluid flow, said fitting orconnector being adapted for attachment of a gauge or measurement deviceto a tubing assembly at said one of said ends.
 14. (canceled)
 15. Amethod of constructing a connector and tubing assembly, comprising:providing a fitting or connector member including a plurality of endswith respective openings that communicate with one another through alumen of said first fitting or connector member, said fitting orconnector member being provided at one of said ends with a gasket bondedto said fitting or connector member so as to form a fluid-tight sealbetween material of said gasket and material of said fitting orconnector member, said gasket being provided with a liquid-impermeablediaphragm preventing fluid flow through said one of said ends, whereinsaid gasket is made of a first polymeric material and said fitting orconnector member is made of a second polymeric material different fromsaid first polymeric material, said gasket being heat fused to saidfitting or connector member so that said first polymeric material ismixed with said second polymeric material at an interface between saidfitting or connector member and said gasket; providing a gauge ormeasurement device; juxtaposing said fitting or connector member andsaid gauge or measurement device so that an access port of said gauge ormeasurement device is in contact with said gasket; and coupling saidfitting or connector member and said gauge or measurement device to oneanother to form a fluid tight seal between said access port and saidgasket so that said gasket and said liquid-impermeable diaphragm isolatesaid gauge or measurement device from direct contact with fluid flowingin said fitting or connector member during use thereof and so that saidgauge or measurement device is operative to measure a physical parameterof the fluid.
 16. The method defined in claim 15 wherein said firstpolymeric material is mixed with said second polymeric material at saidinterface between said first fitting or connector member and said gasketto produce a density or concentration gradient of said first polymericmaterial and an oppositely directed density or concentration gradient ofsaid second polymeric material between said gasket and said firstfitting or connector member.
 17. The method defined in claim 15 whereinthe coupling of said first fitting or connector member and said secondfitting or connector member to one another includes placing a clampabout juxtaposed ends of said first fitting or connector member and saidsecond fitting or connector member and locking said clamping about saidjuxtaposed ends of said first fitting or connector member and saidsecond fitting or connector member.
 18. (canceled)
 19. (canceled)